Described herein are a device which constitutes the equipment, the method of usage for that equipment and the products produced by the device and method. The disclosure herein will not be found in the literature or has not previously been practiced in the field. The literature is of interest for its teachings of the knowledge of skilled artisans at the time of this invention and of the products produced thereby. The claimed invention is a movable support for carrying the material deposition means, a control for moving and activating the deposition means and substrate movable relative to the deposition means and for receiving the material.
Test cells have been manufactured and sold for many home and doctor diagnostic purposes and particularly, pregnancy, strep, AIDS, rubella, influenza and similar conditions. Early detection of the existance of such a condition is of great importance and a simple diagnotic test cell or immunoassay is required. Typically such cells or immunoassay are multi layer structures having several carefully constructed component levels. Each level or layer may have one or more materials such as, bioreagents, target analytes, fluorescent dyes or other responsive ingredients applied to a substrate of a substrate. The arrangement of the layers facilitates a specific biological, optochemical or chemical reaction.
Traditional laboratory testing of specimens requires time and precise handling of the relatively small test specimen. The dangers of time delay to the reagents, loss and improper handling procedures represented serious concerns resulting in increased cost and inaccurate results. In addition, concern for liability, injury and malpractice claims necessitate a more accurate, reliable and convenient technology.
Diagnostic tests that could be performed immediately on almost minute specimens eliminate many of the difficulties and inaccuracies of remote laboratory testing. Diagnostic test assays, cells or strips have to be precisely prepared and made at a relatively low cost to enable wide and successful usage. Confidence in the ability to correctly test with a simple product requires that the test analytes, bioreagent dyes and reactive materials be applied with great precision. Application amount and location are important factors which permit expensive ingredients to be used without concern for waste or the reliability and repeatability of the test product manufactured.
Test cells often rely on color change or the appearance of a specific pattern to indicate a positive or negative result. Whether color or pattern is the indicator, the reaction sought must be dependant primarily on the specimen to be identified. Ambient conditions at the time of manufacture are controlled by the maker of the test cell and are regulated by the Food and Drug Administration. Protective packaging maintains the as manufactured condition of the test assay, cell or indicator.
U.S. Pat. No. 4,912,034 has an apparatus for use in an immunoassay to detect a target analyte in a liquid sample including a porous reactive filter with upper and lower surfaces bound with an antibody specific for a target antigen. Methods of binding include competition for labeled analyte, reaction of a second binding pair member labeled with the bound analyte or detection of an intrinsic measurable analyte property. Although such tests are easy to use and accurate no equipment to accurately and precisely place the reactive material on the filter is disclosed.
U.S. Pat. No. 4,916,056 has a solid phase binding assay to find the amount of analyte in a sample, particularly antigens, antibodies or other ligand or DNA segments. Herein the analyte binding areas capable of simultaneously being contacted by the sample and bioreagent provide readable results. While accurate placement of the bioreagent and/or analyte is important to repeatability, no disclosure of any mechanism to carefully deposit either appears in this patent.
European Patent Application 0 066 648 is a multi layer element analysis for the concentration of specific components using competitive immune reaction including a detection layer and a reaction layer which require careful preparation to be sensitive and reproducible. Test for biochemical changes due to application of substances from the living body detect changes as a result of the amount or concentration of the substance to be found. Even though such a dry test is easier to use than the mixing of liquids, no means for automatically and accurately producing that test in high numbers exists.
Other test apparatus are disclosed in European patent applications 0 217 403 and 0 236 768.